CBN Wheel Selection for a Flywheel Grinder?

I am in the midst of giving my flywheel grinder (FG5000) a facelift and contemplating upgrading to CBN wheels, mfr WVN has a selection of wheels available, but no product info on them. I've never used a cbn wheel on anything, so I'm not sure what to get, is there one wheel to do everything, or do I need multiple wheels?

Any suggestions on where else to get CBN wheels for this machine, besides WVN and Goodsons?

100+ views and no comments, hmmm, no experience here with grinding flywheels with cbn wheels, or did I not phrase my question properly?

Looking at WVN site SUPER ABRASIVE GRINDING WHEELS there are 3 different 6" wheels, one is listed as "rough grit" no grit size given, thru some research I figured out another is "finishing" again, no grit size given. Third is Diamond CBN, no info on rough or finishing, or its application.

Looking at the Goodson site CBN Flywheel Grinding Stones | Goodson Tools & Supplies most are simply labeled CBN wheel, 2 are listed as 60 grit, no grit size listed for the rest. The diamond wheels is described as "Diamond Flywheel Grinding Wheels are designed for use on spray coated floaters and flywheels." Anyone know what they mean by spray coated?

Talking to a rep a few years ago I was given impression that the cbn wheels were a "does all types" wheel, yet according to the Goodson site they are only for cast iron. Question, what happens if you use a cbn wheel to grind a cast steel flywheel?

I've always used silicon carbide wheels in the past, as they were suitable for cast iron or cast steel, no info left on the old blotter, but it looks like a course grit. More than a few vids in youtube showing flywheel grinding with cbn wheels, they grind till face is clean, no switching from roughing to finishing wheels, but I guess that could have been edited out.

WVN and Goodson just supply a niche market, I'm guessing there are other sellers of cbn wheels, short of MSC I'm not sure where else to look. I see cheap cbn wheels from China, but would prefer to deal with an established business that can offer product support, and has some quality control. The wheels I need are cupped wheels with a 1.250" dia center hole, I don't know what grits to ask for.

Since this has been such a popular topic I'll tell you what I've learned. Looked at the Norton catalog and they have cbn wheels that will fit this machine, they come in a vast array of grits, not just course/fine, different bonding densities, different bonding mediums etc, too much info for me to process without a better understanding. I did note that they are suitable for grinding cast iron and steel, although for steel they recommend above a certain Rockwell hardness, 53, 56, 58, something like that, not looking at catalog as I type.

With all the conflicting info I got here, I had no choice but to call wvn, they say their cbn wheels are good for cast iron and cast steel flywheels. The "finishing" wheel is good for general refinishing, the "roughing" wheel is for semi/industrial flywheels with hard spots or grooving where high removal rates are necessary. Still no idea why goodson says cbn is for cast iron only.

I get the fact that most of you know nothing about grinding flywheels, but certainly some of you have more experience with cbn wheels. Question, how do I true a cbn wheel, diamond nib?

dalmatiangirl61 said:

I get the fact that most of you know nothing about grinding flywheels, but certainly some of you have more experience with cbn wheels. Question, how do I true a cbn wheel, diamond nib?

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No info is better than bad info...

I'd continue your search by asking Norton or the other superabrasive manufacturers what their recommendations are for cast iron or steel grinding.

As for dressing, yes, diamond, although sometimes a braked diamond grit wheel is better than a single diamond tip. There's a balance in how aggressive you can be with truing CBN (or diamond), asking the wheel vendor for advice is helpful.

Anyone have had good luck or results dressing or truing a bonded CBN wheel with a single point diamond?
My cbn wheels which are HSS oriented would laugh at such a dress and the dressing diamond is going to give up.
Bob

CarbideBob said:

Anyone have had good luck or results dressing or truing a bonded CBN wheel with a single point diamond?
Bob

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Heck, we should be asking you that. Although I'd guess most of your grinding is with diamond wheels, so how do you true them?

The same as diamond wheels, you attack the bond not the grit and leave supporting tails behind the grain itself.
You want the grit standing tall, sharp and proud so that means taking out bond and leaving the grit.
Various dressing stones of silicon carbide or aluminum oxide, brake or motorized rotary.
Under a microscope these "bond tails" in shape and size are important. Also you do not want to dull the grain top.
Bob

Milland said:

As for dressing, yes, diamond, although sometimes a braked diamond grit wheel is better than a single diamond tip. There's a balance in how aggressive you can be with truing CBN (or diamond), asking the wheel vendor for advice is helpful.

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"Braked diamond grit wheel", I do not know what this is, could you provide a link?

We had a thread that included them just recently that I now can't find... [grrr]

Here's a link to a powered rotary dresser, a braked dresser is similar but uses a friction brake to regulate wheel speed rather than directly powering it.

You are being redirected...

If you use this url you can find a lot of PM threads on dressers and diamond/CBN wheels.

practicalmachinist.com braked dresser - Google Search

I have used the cbn wheels from goodson and rad tech I believe. Pretty much all cast truck flywheels, tractor flywheels, etc. You will want to start off with new coolant and keep it topped off. The time savings using the cbn wheel is well worth the extra $. As for dressing, I have always used the dressing stick provided with the wheel, this of course does not true the wheel like a diamond, but I believe it just may de glaze it, and clean it . You do have to be way more aggressive with a cbn wheel to keep it cutting. Depending on how bad they are grooved etc, I would say I get around 50 to 60 flywheels out of a wheel. Typically some one damages the wheel before its natural life cycle ends.

I don't do flywheels but on a Blanchard I never true a CBN or Diamond wheel unless something is really wrong with the new one.
We will change wheels up to four times a day and just run them. 80 to 1400 grit size and all kinds of fillers. They will true themselves in use.
Depending on the wheel and what is being ground we may stick it every load but when you find the right one for the job and speeds it likes you don't even have to do this.
Finding the right fit for the job unfortunately can mean years of testing wheels so a stick is your best friend.
We have 6 different type sticks on the shelf for varying grits, bonds, and material being ground.

Too soft of a wheel is better than too hard, chasing size and extra wheel cost is better than burning parts.

On the rare times I need true for cosmetics and have very little stock removal to break the newly mounted wheel in I'll use a Norton brake device.
Here like differing sticks you need to have the right stone for the wheel.

The rim (face) widths I see for your grinder are very narrow, these will true themselves up very quickly.
Bob

I've used wheels from Goodson and Radiac. I haven't needed to dress for any reason. Just recently learned that they will cut much more aggressivly if you use only a trickle of coolant. When finishing use more coolant to get a smoother finish.
Max